A new order creation error code when there's been a change in the offer's price

Occasionally, an airline could refuse order creation due to the selected offer's price having changed since it was last retrieved. Previously, this sub-category of airline failures used to result in the more general offer_no_longer_available error being returned from our API. The appropriate course of action for handling this error was to restart the search flow (by creating a new offer request).

We've now introduced a new price_changed error code, which lets you know it may be possible to, instead of starting a new search, simply retrieve the most up-to-date information about the offer and retry order creation with the updated total_amount. This simpler flow opens the door to more flexible ways to address failures.

Please note that airlines' pricing and booking systems can sometimes be out of sync, which would mean retrieving the offer after a price_changed offer would not show a change in price. We are aware of the issue and are looking to mitigate its effect to the best of our ability.